A general wireless communication system includes a plurality of transmission antennas based on a cell, and uses various MIMO (multiple-input and multiple-output) techniques. For example, techniques such as OL-MIMO (open-loop MIMO), CL-SU-MIMO (closed-loop single-user IMO), CL-MU-MIMO (closed-loop multiple-user MIMO), Multi-BS-MIMO (multiple base station MIMO), and the like, may be used.
In general, a system in which all the antennas are installed and operated in a base station (BS) is called as a centralized antenna system (CAS). Known characteristics of a CAS are a path loss and shadowing effect with respect to each antenna are substantially the same because distances between antennas are short relative to a cell radius of a BS. Also, in case of a CAS-based communication system, since link quality of a terminal is different according to a distance between the terminal and a BS, there may be a significant difference in throughput performance between an inner cell user and a cell-edge user.